I may write a script following ucl2.xml on my storable sdcard.But,I'll try it. Because according to point 5 from blow picture.we know it was running uboot_mfg,and had host PC. but now ,our application scenario have not PC ,and using sdcard update nand flash . In other words and last, according to ucl2.xml, I know how to write shell script when Updater state ,but not when BootStrap state.